...and go to "Events" listed on the left hand side.
See if this link works.
Thursday - Sunday, June 1-4 -- 16th Annual Buick Raceday 2006 For full event information and pre-registration, visit www.mi-buicks.com or www.buickperformancegroup.com for information regarding the Thursday Test and Tune and Friday’s fun matches. Event flyer and Pre-registration form.